The present invention relates to appliances for treating teeth, particularly human teeth.
In particular, the present invention relates to an apparatus to be utilized for applying to teeth a reinforcing acid-resistant layer of a tooth decay retarding agent. The invention relates especially to an apparatus which is capable of exposing teeth to the radiation of ultrasonic waves while the teeth are engaged by the decay retarding agent.
In order to prevent or retard tooth decay, it has already been proposed to apply manually to the teeth which are to be treated a solution of a tooth decay retarding agent such as tin fluoride, sodium fluoride, or fluoramine. However, if only the decay retarding agent is coated on the surface of the teeth, the coating adheres poorly to the teeth and is readily dissolved away and removed from the tooth surface in a relatively short time. Thus, through measures of this type it is impossible to achieve a long-lasting decay-retarding effect. Moreover, if a coating of a tooth decay retarding agent is situated only at the surface of the teeth, it is not possible to achieve also an effective prevention of dissolving of calcium from the tooth surface.
It has been discovered, however, that the above drawbacks can be eliminated if the teeth are exposed to the radiation of ultrasonic waves while the teeth are engaged by the tooth-decay retarding agent. However, an apparatus for effectively carrying out such a treatment has been difficult to develop. Thus, a tray for receiving the teeth while the latter are engaged by the decay retarding agent has been developed, this tray having a hollow interior containing a liquid medium for transmitting the ultrasonic vibrations. However, when a vibrating means is attached to such a tray, unavoidable difficulties are encountered in connection with preventing the liquid medium from receiving air or air bubbles or from spilling undesirably, so that the desired results are difficult to achieve with such an apparatus.